Two organic acids isomers, 3‐isopropylmalic acid (3‐IPMA) and 2‐isopropylmalic acid (2‐IPMA), were identified and quantified in wine samples by using an LC–MS/MS method without any chromatographic separation, but processing the MS/MS data with a recently developed deconvolution algorithm (LEDA: linear equations deconvolution analysis), thus decreasing the time necessary for the process. In particular, the LEDA tool processes the MS/MS signals and assigns the relative concentrations (abundances) of the isomers in the sample, at the mg L⁻¹ level. The efficiency of MS/MS signal assignment was improved by introducing five linear equations to define the LEDA matrix. Then, as a novel approach, an overdetermined system of linear equations was applied for the deconvolution of isomers. The use of LEDA to identify and quantify the isomers in wine samples, together with the choice of a short LC column and a fast elution gradient, simplifies the process and shortens the time needed. Furthermore, it was evaluated the quantitative determination of the IPMA isomers by using the calibration curve provided by the precursor ion MRM transition data. The calculated values of accuracy (recovery between 82.6% and 99.8%) and precision (RSD between 0.4% and 4.0%) confirm the validity of this quantitative approach and the ability of LEDA to establish the correct percentage of the MS/MS signal for each isomer. Finally, to compare the conventional LC–MS/MS method and our proposed method of LC–MS/MS coupled with LEDA post‐processing elaboration, a series of real wine samples were analysed by both methods, and the results were compared.

中文翻译：

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通过MS / MS解卷积分析测定葡萄酒样品中的共洗脱异构体。

使用LC-MS / MS方法在葡萄酒样品中鉴定和定量了两种有机酸异构体，即3-异丙基苹果酸（3-IPMA）和2-异丙基苹果酸（2-IPMA），并进行了色谱分离，但使用了MS / MS数据使用最近开发的解卷积算法（LEDA：线性方程组解卷积分析），从而减少了处理所需的时间。尤其是，LEDA工具可以处理MS / MS信号，并以mg L ^-1分配样品中异构体的相对浓度（丰度）水平。通过引入五个线性方程式定义LEDA矩阵，提高了MS / MS信号分配的效率。然后，作为一种新颖的方法，将超定线性方程组应用于异构体的反卷积。使用LEDA鉴定和定量葡萄酒样品中的异构体，以及选择较短的LC色谱柱和快速的洗脱梯度，可简化过程并缩短所需时间。此外，通过使用前体离子MRM跃迁数据提供的校准曲线，评估了IPMA异构体的定量测定。精度（回收率在82.6％和99.8％之间）和精度（RSD在0.4％和4之间）的计算值。0％）证实了这种定量方法的有效性以及LEDA为每种异构体建立正确百分比的MS / MS信号的能力。最后，为了比较传统的LC-MS / MS方法和我们提出的LC-MS / MS方法以及LEDA后处理工艺，使用这两种方法分析了一系列真实的葡萄酒样品，并将结果进行了比较。